Technical Field
The present disclosure relates to a bead immobilization method and bead arrays made thereby.
Description of the Related Art
Nanoarrays and microarrays used in the biotechnology, pharmaceutical, and medical industries are generally formed by immobilizing reactive and sensing chemical entities on substrates in spatially addressable arrays. Conventional immobilization technologies for forming such arrays can be broadly categorized as photolithography and spotting technologies.
Photolithography technology synthesizes arrays of chemically modified sites in situ on substrates using photolithography and combinatorial chemistry. Problems with this immobilization technology are the expense, complexity, and time associated with multiple irradiation, masking, and chemical reaction steps.
Spotting technology deposits droplets of chemical reactive/sensing solution over the surface of a substrate or into wells formed in the substrate. Problems with this immobilization technology are poor precision and reproducibility, and low signal-to-noise ratio. Droplets on the surface of the substrate can interfere with adjacent spots causing contamination. The density and uniformity of each spot is not easily controlled. A solidifying agent around the perimeter of a spot portion can cause non-specific adsorption of droplets on the substrate and decrease the signal-to-noise ratio. The signal-to-noise ratio of luminescence from surface spots or droplets confined in wells is reduced by the background noise of luminescence from the substrate itself.
A need therefore exists for an immobilization technology for forming nanoarrays and microarrays that is generic, simple, and low cost, yet has improved precision, reproducibility, and sensitivity.